HIV-1 infection is often monitored by measuring the levels of plasma viremia; however, this information does not correlate to the levels of virus detected in other compartments of the body. These reservoirs of virus include follicular dendritic cells, lymphocytes, and macrophages, and may also include thymus, bone marrow, and the central nervous system. Currently the only techniques available for evaluating the presence of HIV are invasive and require specialized processing techniques such as in situ hybridization, which is available only in research laboratories. In this project we used a deoxyfluorothymidine (FLT) combined with a radioactive marker (18F) as an imaging agent with positron emission tomography (PET) scanning to identify tissues that are sites of HIV replication. The radioactivity produced by this agent has a half-life of 2 hours, and the radiation exposure of the tissues is well within the limits experienced by patients injected with radiotherapeutics for clinical use. Four M. nemestrina were assigned to this project, two uninfected controls and two infected with HIV-2. The scanning images appear to highlight areas of lymphoid tissues in the infected macaques as well as other sites of apparent high mitotic activity, possibly indicating sites of virus replication. These encouraging results indicate that more study is warranted.